The near-300 schoolgirls were abducted from their state boarding school in Chibok, Borno state, almost a month ago. The majority are believed to be Christian.

The girls have been 'converted to Islam' according to the Boko Haram leader

The girls are seen wearing black and grey Islamic dress called a chador (loose cloak) in an undisclosed rural location.

Immediate reports said that around 130 are present in the video. Two standing at the back of the crowd of girls hold a black flag, and the rest are heard chanting and singing.

Three girls are interviewed for the video in total. According to the BBC, two girls say they were Christian and have converted to Islam, while the other says she is Muslim.

The camera pans to one of the girls, speaking directly to camera

All appear to be calm, but as one girl speaks direct to camera her eyes flick nervously to the side of the screen as she murmurs. Another said that the girls had not been harmed.

In the right-hand corner of the screen is Boko Haram's logo, a picture of the Koran with two AK-47s crossed in front of it.

Shekau never appears with the girls but is filmed in front of a neon green canvas backdrop, carrying an automatic weapon.

The Boko Haram leader had threatened to sell the girls "in the marketplace" in a previous video for a bridal price of as little as £12.

The Boko Haram leader appears for 17mins in the video, but never in the same shot as the girls

Kashim Shettima, Borno state's governor told the BBC earlier on Monday that he had received sightings of the girls and the military were currently pursuing promising leads.

"We've got reports of them being sighted in some locations – which we have conveyed to the relevant military authorities, for them to cross-check, verify and get additional information on the accurate location of the daughters," he said.

A team of UK experts is currently in Nigeria to help with the hunt for the schoolgirls. A Foreign Office spokesman said: "The team is drawn from across government, including the Department for International Development, Foreign and Commonwealth Office and Ministry of Defence, and will work with the Nigerian authorities leading on the abductions and terrorism in Nigeria.

"The team will be considering not just the recent incidents but also longer-term counter-terrorism solutions to prevent such attacks in the future and defeat Boko Haram.

"The team will be working closely with their US counterparts and others to co-ordinate efforts."

Prime Minister David Cameron told the BBC's Andrew Marr show on Sunday that it was unlikely Nigeria would ask for British troops, but added: "I rang the Nigerian president to offer anything that would be helpful and we agreed to send out a team that includes some counter-terrorism and intelligence experts to work alongside the bigger American team that's going out there."